if I remeber correct teh space.com-So it might be interesting to watch if t/Space will enter the competition for the fuel depots.

I think the prize would have to bigger before T-Space would compete because the launch costs for the modified larger version quick reach are likely to be a lot more than a couple of million.

I think that NASA would have to sweeten the deal a bit with a bigger prize, guaranteed contracts or agree to subsidise the launch somehow before they get many takers.

Another thing to think about is that these prizes will not be looked at in the same way as the X-prize was. There was international competition where national pride would have played a part, I'm not sure foreign teams will be eligable for centennial prizes.

You have to ask the question why anyone would want to enter a competition where the prize is a lot less than the cost of competing if there is nothing else to be gained.

The x-prize pitted countries against each other and there was the promiss of a tourist market. What else is on offer here to tempt people?

_________________A journey of a thousand miles begins with a single step.

I haven't thought about your last question yet but it is a very essential one I think.

Here I simply want to consider the question of t/Space to be a competitor more precisely.

My thought is that t/Space's CEV concept consist of several elements and components. Their tankers consist of the tank for the porpellent to be delivered, the engine, the tank for the propellant the engine will use and the airplane to launch the tanker.

The tank for delivering propellant in principle is a component which can be considered separated from the engine, its tank and the airplane - it may be that t/Space has developed a special design and technology for that tank.

They might consider a Centennial Challenges Prize for fuel depots as an opportunity to make real this part of their concept in a subscale-version.

To do so they could win a prize and the work invested into the design and development wouldn't be wasted.

Since SpaceX will have developed tanks for launches only but ot for delivery- and depot-purposes they might be the right servicer to carry each competitor's tank/fuel depot to any orbit - if it doesn't exceed the payload capacity of the Falcons.

The QuickReach wouldn't be required and the depot simply would have been derived from the designed tanker - which would mean to make the CEV concept reality partially: If it turns out that the real fuel depot works well then it would be the first step to a future tanker in the eyes of t/Space. I would like to see them compete. Do I remeber correct that they said that there might be other chances than the contest and fly-off NASA had in mind originally? This would be one.

Looking at the competition rules for on-orbit fuel storage a little closer, it seems like NASA is asking a lot for their money.

Competitors are required to put a minimum of 140kg of propellant (20kg H2 and 120kg O2) into a LEO (above 200km) for a duration of 120 days.

On the surface this seems not to be to bad but when you think about it the duration causes a lot of problems in LEO. Either the Fuel Depot would need to reboost itself regularly or the orbit would need to be much higher so that it hasn't decayed to lower than 200km after 120 days. This means that the Fuel Depot would probably need its own engine and energy source (probably solar panels) which will all add to the cost and weight.

Probably using a small solar powered ion engine running on the stored H2 would be a good solution as it would require only a small amount of propellant and would enable boosts over a long period of time between refuelling.

Some sort of RCS would also be needed to keep the Fuel Depot from tumbling and keep it orientated correctly as well as insulation to minimise boil off.

The rules do allow the production of propellant in orbit, so it would be possible to send it as water and make it up there but I think that this would increase the weight further and add unnecessary complexity.

Given the above I can easily see a Fuel Depot weighing 500kg (especially if the propellant masses are increased to take into account boil off) which would require something like a Falcon I launch at $6.7m. By the time you factor in the development costs in man power and testing, this doesnt look very attractive for a would-be competitor.

Although I have not looked at the other challenges to closely I think they are similar in their expectations for the cash prize provided. Its one thing to ask a team to spend a few tens of thousands of dollars to get a $50k climber or tether prize (some universities would spend this on a research project without a prize) but quite another to expect an organisation to spend maybe $10m to get a prize of $5m without anything else on offer.

_________________A journey of a thousand miles begins with a single step.

It's unknown yet how much time will be spent before any competitor has ready the demonstrating fuel depot. Virgin Galactic has increased the size of the White Knight as Soyuz said in another thread - he linked to an article in which Virgin Galactic is quoted to have said that the increase is due to their intention to do orbital launches.

So if a demonstarting fuel depot is ready after the increased White Knight is ready then the White Knight could be used perhaps.

Virgin Galactic have said that they will begin their operations in late 2008 which is less than three years from now. If a demonstrating fuel depot is ready later than that time then the increased White Knight could be used. This might be interesting for t/Space because it would be a first test for the air launches of their concept.

Informations about the weight, size and payload-capacity of the increased White Knight would be very interesting as well as other informations about it.

Dipl.-Volkswirt (bdvb) Augustin (Political Economist)

EDIT: Please remember - a suborbital flight launched via the increased White Knight 2 has the maximum price of $ 200,000 only. White Knight 1 could carry up to 8,000 pounds which are more than 3,000 kg if I am correct. The demonstrating fuel depot weighing 500 kg only would leave at least 2,500 kg for a second stage as booster for a launch from 14,000 meters altitude.

EDIT2: And an additional hint might be that the QuickReach Airlaunch LLC. is developing presently is designed to boost 1000 pounds which is around 500 kg if I remeber correct.

Well, if you remember, SpaceshipOne was a demonstrator vehicle. And after the $10 million, MAV didn't get anything more from the X-prize foundation.

The extra incentive was the $100m contract from Virgin. If NASA (or someone else) were to add a promise of such a contract for fuel storage in orbit they would get many more takers.

The difference is that while x-prize teams could be pretty sure that there was a tourist market to make additional money from, I'm not sure the same can be said for fuel storage. It is unclear whether NASA would buy fuel storage services in the future, at this time their whole program is at the whim of politicians who could cancel it in the next couple of years or change the emphasis so that fuel storage would not be desirable. Long term private companies might want it but the timing isn't right at the moment.

_________________A journey of a thousand miles begins with a single step.

Might it be that NASA has something in mind which they don't make public yet?

Orbital fuel depots are of use and purpose only if there is something in space which needs this fuel.

This can be satellites but these need something to get access to a depot - so either there has to be a small vehicle docked to the satellite or the depot or the satellite has to be capable to approach the depot or the depot is able to approach the satellite.

Already orbiting satellites can't do all this. So if the fuel depots can't approach nothing what then can make use of them?

1. The ISS ca use them for altitude corrections and adjustments.
2. What if NASA internally has in mind space vehicles which leave and enter earthian orbits but never land on Earth? They would have to be refueled in orbit - id est by fuel depots. Might there be the idea to leave a CEV in orbit one day and only to launch a space departure stage for each flight which is left empty and fueld in orbit?
3. What about the possibility that the fuel depots will be used in lunar orbit to fuel or refuel the landers futurely?

future/futurely mean flights after the first lunar flights have been done which are said to begin in 2014 if I remember correct. NASA might be stimulated by t/Space's CEV-concept.

It makes the point that NASA has tried such commercialisation in the past only to abandon it leaving companies up s**t creek without a paddle so prospective competitors are likely to be wary about treading the same path again.

Looking at the Low-Cost Space Pressure Suit Challenge it would be easy for a competitor to spend a few hundreds of thousands of dollars to demonstrate compliance. The requirement for them to actually sell 10 suits before they are eligable (one assumes that NASA would not buy them itself as this could be cited as being unfair by losing teams) seems a bit much. A suit would either meet the requirement or not, why make its commercial performance part of the deal?

_________________A journey of a thousand miles begins with a single step.

It is really quite dissappointing how few articles and how little information is out there on what is currently going on for each prize. NASA's publicity machine is absolute crap, they find a partner for each prize and then basically forget about them. A bit of promotion wouldn't hurt and might get more people interested.

The issue with the prizes is that, like it or not, NASA is still limited by the people in the organisation making the decisions. Unlike the X-Prize, the rules for which were quite straightforward and easily understood, the NASA prizes have been implemented (not originally designed), and will reflect the internal culture of that organisation ie. bureacratic, hence difficult to understand or implement or lacking in practicality.

I'm not saying they all are, but I'll bet at least some of those characteristics will impede the development of the prizes so as to make them unpractical or unattractive to potential participants. Excessive oversight and paperwork by NASA or a related Government body would be the first indication.

It is really quite dissappointing how few articles and how little information is out there on what is currently going on for each prize. NASA's publicity machine is absolute crap, they find a partner for each prize and then basically forget about them. A bit of promotion wouldn't hurt and might get more people interested.